Suspension spring



FIG. 1 is a perspective view showing the top, front, and right side of a suspension spring having the inventive design;

FIG. 2 is a top view of the suspension spring shown in FIG. 1;

FIG. 3 is a front elevational view of the suspension spring shown in FIG. 1 and the back elevational view is identical to the front elevational view;

FIG. 4 is a right side elevational view of the suspension spring shown in FIG. 1 and the left side elevational view is identical to the right side elevational view; and,

FIG. 5 is a bottom view of the suspension spring shown in FIG. 1.

The broken lines showing on the flanges in FIGS. 1, 2 and 5 is included for the purpose of illustrating environment and forms no part of the claimed design. 

The ornamental design for a suspension spring, as shown and described. 